Mechanical sound waves are unable to travel through a vacuum such as through space but radio waves are transmitted to earth from satellites how is this possible

What color would an object that reflects green and blue light appear to be in white light? a. blue b. cyan c. magenta d. black

Akg a of 55 m at an of 11 ? . if is at 98 km/h,be ?

Two cannon balls weighing 18 kg and 24 kg are chained together and fired horizontally with a velocity of 165 m/s from the top of a 21-m wall. the chain breaks during the flight of the cannonballs and the 18-kg cannonball strikes the ground at t = 1.5 s, at a distance of 240 m from the foot of the wall, and 7 m to the right of the line of fire. determine the position of the other cannonball at that instant. neglect the resistance of the air.